The long-term objective of this research is to develop a rapid, cost-effective test for human antibodies to Hepatitis B core antigen (HepBcA) which would be suitable for predonation screening of blood donors, and would utilize novel capacitive affinity sensor technology. The specific aims of this research are: 1) to evaluate methods by which HepBcA can be immobilized on the surface of the biosensor, 2) to evaluate a human serum protein as a coating for a reference biosensor, and 3) to determine the magnitude and specificity of the capacitance changes when HepBcA- and human serum protein-coated biosensors interact with mouse monoclonal and human antibodies against HepBcA. This project will contribute to technological innovation by assessing the applicability of capacitive affinity sensor technology to a major current problem for blood banks: the high cost of testing for antibodies to HepBcA, a surrogate test for non-A, non- B hepatitis. Developing a HepBcA antibody test suitable for predonation screening of donors should have substantial commercial potential, both in the U.S. and in several foreign countries.